ABB Relion 650 Series Communication Protocol Manual page 43

1MRK 511 379-UEN A
UV
WEI
VT
3I
O
3U
O
Communication protocol manual
irregular rotation, on which UT1 is based. The Coordinated Universal
Time is expressed using a 24-hour clock, and uses the Gregorian
calendar. It is used for aeroplane and ship navigation, where it is also
sometimes known by the military name, "Zulu time." "Zulu" in the
phonetic alphabet stands for "Z", which stands for longitude zero.
Undervoltage
Weak end infeed logic
Voltage transformer
Three times zero-sequence current.Often referred to as the residual or
the earth-fault current
Three times the zero sequence voltage. Often referred to as the
residual voltage or the neutral point voltage
Section 8
Glossary
37